Fibromyalgia: increased reactivity of the muscle membrane and a role of central regulation

E.G. Klaver-Krol (Corresponding Author), Johannes J. Rasker, M. Klaver, Peter M. ten Klooster, M.J. Zwarts

Research output: Contribution to journalArticleAcademicpeer-review

8 Citations (Scopus)
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Objective: Fibromyalgia (FM) is characterized by widespread muscle pain and central neural deregulation. Previous studies showed increased muscle fiber conduction velocity (CV) in non-painful muscles of FM patients. This study investigates the relationship between central activation and the CV in FM.
Methods: Twenty-two females with primary FM and 21 controls underwent surface electromyography of the non-painful biceps brachii. Mean CVs were calculated from the motor unit potential velocities (CV-MUPs), and the CV-MUPs’ statistical distributions were presented as histograms. The amount of muscle activity (average rectified voltage, ARV) was measured.
Results: The CV was higher in the FM-group than in the controls (P=0.021), with CV-MUPs generally shifted to higher values, indicative of increased muscle membrane propagation speeds. The largest increase in the CV of the FM-group occurred when adopting and maintaining a limb position at only 5% of maximum strength (P<0.001); the CV did not, as normal, increase with greater force. However, the ARV in both groups similarly increased with force.
Conclusions: In fibromyalgia patients, the muscle membrane propagation speed increases independently of the force load or amount of muscle activity produced. When adopting a limb position, the patients show an augmented muscle membrane reaction, suggesting deregulation from higher neural centers.
Original languageEnglish
Pages (from-to)12-19
Number of pages8
JournalClinical neurophysiology
Issue number1
Early online date31 Oct 2018
Publication statusPublished - 1 Jan 2019

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